Whale season started this month on the Brazilian coast and is expected to last until November. Projeto ProFranca Director Karina Groch reported that, for right whales, the season started a little early. The first specimens were reported on June 12. “Since then, the number has been on the rise,” Groch said.
On July 16, hovering over the coast of Santa Catarina state, south Brazil, researchers sighted more whales in the region than the whole month of September last year. “This is a sign that we’re likely to see a season with a higher number of whales than last year,” the biologist argued.
In September 2020, the peak of the season, 42 right whales were observed on the coast of Santa Catarina (33) and Rio Grande do Sul (9). This year, in the same area, 36 whales have been spotted with the aid of drones. This species, Groch pointed out, has experienced a yearly 4.8 percent growth.
The right whale is a species threatened with extinction. It was hunted for four centuries and started returning to the Brazilian coast early in the 1980s. In 2018, a peak of occurrences was observed – a record-breaking 273 right whales on the Santa Catarina coast.
The researcher explained that the floating numbers are linked to the species’s reproductive cycle, which happens every three years, when females come to the Brazilian coast to give birth.
This movement is also connected to the availability of food in Antarctica. “In years with more food, more whales come here; in years with less food, fewer whales come, as they come specifically to give birth to their young,” the director explained.
The main reproductive area of the right whale in Brazil is the mid-southern coast of Santa Catarina, where there is a federal conservation unit for the species.
Population Forecasts
The main flight for identification through photography, population estimates, and young growth surveillance is scheduled for September. Groch reported that yet another line of research, initiated last year and sponsored by Petrobras, aims to collect skin in a bid to identify the whales’ feeding areas.
Historical evidence has been seen linked to hunting, Groch went on to state, as well as recent evidence, through photographs of a whale and the satellite surveillance of another female, that the whales that come to Brazil probably feed during the summer near the South Georgia Islands. There are, however, other areas where the ProFranca team wishes to survey. “It’s key to species conservation that we try and find which other areas they occupy.”
At least 550 female right whales breed regularly in Brazil. Due to the three-year reproductive cycle, these are not the same whales that come to the Brazilian coast. Furthermore, they share other reproduction areas. They also go to Argentina, where approximately 13 percent of the whales cataloged in Brazil have been at least once. The collection of the skin of these cetaceans provide researchers with a sign as to where they feed.
Groch explained that the big whales that come to Brazil more often, especially the right whale and the humpback whale, are migratory species located between feeding and reproduction areas, in warmer water. “In the summer, they feed in regions closer to Antarctica, near the South Georgia Islands and in other areas we intend to discover.”
The Humpback Whale
Also initiated this month was the 13th breeding season of the humpback whale in Brazil, with the reoccupation of old breeding areas, with a higher concentration in the Abrolhos bank, in the southernmost tip of Bahia, and northern Espírito Santo. “Seventy percent of the population are in this region,” said Enrico Marcovalido, coordinator of the Projeto Baleia Jubarte (“Humpback Whale Project”).
There is growth in other areas, though. Until last year, whales would spread from São Paulo to Rio Grande do Norte. This year, to the surprise of scientists, they are also appearing in Santa Catarina and Rio de Janeiro. “We’ll keep monitoring. Wherever the whales go, we go right after,” Marcovaldi pledged.
Late in the 1990s, during the implementation of the Abrolhos Sea Park, researchers discovered a small amount of humpback whales from a population nearly decimated by hunting. “It was an immense surprise and joy,” Marcovaldi said.
The population estimated to total a thousand to 1.5 thousand specimens in the 1990s, escalated today to 20 thousand humpback whales. Last year, in the Abrolhos region, the project covered 798.8 nautical miles in 23 days. In this time span, 171 groups totaled 433 whales, of which 76 were baby whales.
Studies
The Projeto Baleia Jubarte, also supported by Petrobras, comprises a range of lines of research. There is data and material collection to subsidize conservation policies. “We gather knowledge to keep society at large informed.”
Through photography, we identify each whale by the central part of its caudal fin, which presents a pigmentation pattern ranging from white to pitch black. “It’s like people’s finger prints.”
In the last 30 days, the project’s identification base included more than 6 thousand whales. Researchers also collected small pieces of skin and grease from the whales to analyze genetic material, contaminants, and sex.
There is also an aerial census to estimate population sizes, run every three years. Another recent research line is photogammetry, aided by drones, to predict whales’ health and local characteristics. Beautiful footage is produced during research in order to raise society’s awareness regarding the conservation of these cetaceans.
Another key initiative in the preservation of the humpback whale is watching tours over in coastal Bahia and Espírito Santo, with a number of trained and monitored partners.
“We believe it’s a great tool for monitoring, because it brings added economic value to the whales. It generates employment and income, raising awareness. This comes against any threat stemming from hunting. We prove whales are worth a lot more alive than dead,” Enrico Marcovaldi stated.
This season, the humpback whale is benefited by the partnership with Australia’s Griffith University through an in-depth assessment on their nutrition. The goal is to ascertain whether the whales are well nourished and to use humpback whales as sentinels to gauge the impact of climate change on Antarctica.
ABr